1. Field of the Invention
The present invention relates to door mirrors of a motor vehicle and more particularly to an electrically operable pivoting actuator for the door mirror of the motor vehicle.
2. Description of Related Art
Folding of the door mirror relative to a motor vehicle is necessary in many situations. A folding over of the door mirror relative to the body of the car is occurred when, for example, an obstacle hits the door mirror from a rear position in which an angle from the fold-over position of the door mirror to the normal, operational position is defined as angle β. Further, a folding in of the door mirror relative to the body of the car is occurred when, for example, parking in a narrow space in which an angle from the normal, operational position to the fold-in position of the door mirror is defined as angle α.
Designs about angle α and angles β are well known. For instance, U.S. Pat. No. 6,130,514 disclosed an electrically operable pivoting actuator comprising a mirror base 11, a frame 12 fitted with the mirror base 11, a coupling gear wheel 26 sleeved on a base shaft 101 of the mirror base 11, a coupling member 30 on top of the coupling gear wheel 26, noses 32 and recessed portions 28 for providing a couple-limited claw coupling between the coupling member 30 and the coupling gear wheel 26, projections 31, fingers 103, and key ways 104 for providing a rotational securing and axial freedom of the coupling member 30 relative to the shaft 101, a helical spring 40 for exerting an axially downward directed pressure on the coupling member 30, an electromotor 20, a transmission system 21 coupled between the driven shaft 20' of the electromotor 20 and the coupling gear wheel 26, stop means including an annular top face 150, an inner ring 151, an outer ring 152, a first ring segment-shaped groove 153, inclined end faces 154 and 155, a second ring segment-shaped groove 156, inclined end faces 157 and 158, a first nose 159, inclined side faces 160 and 161, a second nose 162, inclined side faces 163 and 164, an annular top face 250, an inner ring 251, an outer ring 252, a third ring segment-shaped groove 253, inclined end faces 254 and 255, a fourth ring segment-shaped groove 256, inclined end faces 257 and 258, a third nose 259, inclined side faces 260 and 261, a fourth nose 262, and inclined side faces 263 and 264, and other associated means.
Components of the mirror base 11 and the frame 12 are caught when the extreme fold-out or fold-in position of the door mirror is reached. At this moment, the noses 32 fitted in the recessed portions 28 for enabling the coupling member 30 to move axially until contacting the detection means 300 thereunder. As a result, the detection means 300 is activated to stop the electromotor 20 for preventing further actions of the components from occurring as a safety means.
The desired angle α and angle β can be achieved by the patent mainly by the provision of ring segment-shaped grooves, noses, etc. However, it is known that there are a variety of shapes about the body of the car. As such, angle α and particularly angle β of one car can be different from that of the other car. Hence, it is often that ring segment-shaped grooves and noses are unique to one specific model of the car. In other words, mass production of a door mirror having the above electrically operable pivoting actuator is made impossible. As a result, the manufacturing cost is relatively high. Hence, a need for improvement exists.